This invention relates to the field of baskets or pots for potting nursery plants. Such containers hold soil or a growth medium, and serve to support and restrain the plant root structure from its initial sprouting through continued growth. The container also provides for ready transportation of the plant, and should provide for easy transplanting of the plant into the ground.
U.S. Pat. No. 4,223,480 to Welty is the closest known prior art in regards to removable inner liner for potting a plant and transplanting the same. This patent discloses a perforated, sectionalized liner made of flexible material, folding upwards or away from a base member. A group of finger members permits the ready removal of the enclosed liner with its contained potting soil and root ball from a pot and the subsequent removal of the root ball from the liner.
U.S. Pat. No. 2,960,798 to Linstaedt discloses a nursery pot constructed of an outer metal mesh reinforcing material and having, as a liner, tar paper (asphaltum felt). This construction provides an impermeable, decoratable pot.
U.S. Pat. No. 4,106,235 to Smith discloses a two section, inner and outer pot construction where roots are intended to grow through the inner pot mechanism. However, this structure is designed specifically for hydroponics and utilizes a porous inner pot bottom (screen) through which the roots can grow into a hydroponic medium.
U.S. Pat. No. 2,142,324 to Magyar, Jr. discloses a potting system in which a pot liner is provided with an inner and outer sleeve, rotatable to permit the plant roots to extend through the walls of the pot. The entire construction is rotated open for transplanting and planted, pot, root ball and all. The pot of this patent is therefore properly considered part of the root ball.
U.S. Pat. No. Des. 250,940 discloses a visual depiction of a Plant Container having a spaced distance from an inner liner to the base of the container.
U.S. Pat. No. Des. 255,555 likewise discloses a pot having an apparently porous inner liner spaced a distance from the bottom of the pot and additionally apparently includes tubes vertically ascending from the base of the pot through the screen into the upper, root ball area of the pot which are hollow and which have periodically spaced holes.
U.S. Pat. No. 879,613 to Edwards discloses an early transplanting basket in which the root ball is suspended within a coarse metal mesh basket. The entire outer surface of the root ball is exposed to the air rather than just those root tendrils which penetrate through the lining.
U.S. Pat. No. 4,027,429 discloses another form of pot in which an inner ring within the base of the pot creates a spaced annular water reservoir in the bottom of the pot upon which is placed, loosely, a soil supporting disk which supports the soil and the plant. The bottom of the pot is open and the disk can be pushed upward through the bottom of the pot to remove the soil or root ball for planting.
None of these patents disclose a structure in which the soil is contained within a permeable soft plastic membrane, enclosing the root ball but through which the roots can grow, permitting roots to air prune at the far tips only without exposure of the rest of the root system within the root ball to air, the ball being supported within a wire basket which minimizes inhibition of root growth, but which supports the liner and its contained liner with root ball for free air circulation.